207 results about "Bioleaching" patented technology

Methods and apparatus are disclosed for recovering metals from metal-containing support materials such as mineral ores. In one embodiment, the metal may be separated from crushed support material or ore in a bioleaching lagoon by the action of hydrocarbon-utilizing bacteria under anaerobic conditions. The bioleached material is then pumped into a precipitation lagoon where hydrocarbon-utilizing bacteria oxidize the metals under aerobic conditions. In another embodiment, metals may be directly biooxidized from a heap of the metal-containing support material having a hydrocarbon/oxygen injection system embedded therein. A water sprinkler system may be used to wet the heap while the hydrocarbon/oxygen injection system stimulates the growth of hydrocarbon-utilizing bacteria. The resulting effluent solution may be pumped or gravity fed to an aerobic precipitation lagoon where aerobic hydrocarbon-utilizing bacteria are used to precipitate or otherwise deposit the metals onto a deposition material.

The invention discloses an air-lift bioreactor, with internal recirculation, for producing sulfide-ore and minerals bioleaching solutions, with a phase-separating and solids-recirculation system without needing to impel the suspension containing the solids to the bioreactor by means of pumps, using diatomaceous earth and/or ferric precipitates as solid support to immobilize iron and sulfur-oxidizing microorganisms. Specifically speaking, the invention describes a bioreactor that continuously produces bioleaching solutions containing microorganisms for inoculation and irrigation of sulfide-ore heaps and dumps processed by bioleaching. The bioreactor is stirred pneumatically, and is generally made up of an air diffuser, a reaction zone, a de-gasification zone, a solids separation zone, a culture media inlet, and a bioleaching solution outlet. Depending on the source of energy supplied for the growth of microorganisms, the bioreactor can produce a solution concentrated in ferric ions, iron-oxidizing bacteria and reduced-sulfur-compound-oxidizing bacteria.

A method of extracting zinc from a sulphidic ore is provided which comprises bioleaching the ore in a heap with acidophilic microorganisms to produce a pregnant leach solution which is recovered from the bottom of the heap. An integrated process which comprises subjecting the pregnant leach solution to neutralization and solvent extraction to produce a concentrated zinc solution is also provided. Zinc may be recovered from the concentrated solution by means of electrowinning, either in the absence or presence of manganese. Alternatively zinc may be recovered in the form of a zinc compound.

The invention discloses a compound bacterium community capable of efficiently leaching a sulphide ore, and a compounding method and an application method thereof, and belongs to the technical filed of wet-process metallurgy. Aiming at a biological leaching mechanism of the sulphide ore and the physiological-biochemical characteristics of microorganisms, a community capable of efficiently leaching the sulphide ore is compounded by a plurality of mineral leaching microorganisms, wherein the mineral leaching microorganisms comprise marine bacteria which come from deep-sea hydrothermal vents and are capable of enduring high concentration sodium chloride, sulfur-oxidized bacteria, iron-oxidized bacteria and archaea which are from a freshwater environment, autotrophic bacteria and facultative heterotrophic bacteria. Not only can the difficult problem that the mineral leaching microorganisms from the freshwater environment are intolerance of sodium chloride be solved, but also microorganisms required by oxidation and dissolution of the sulphide ore and diversity of chemical reactions are guaranteed. The compound bacterium community can obviously increase leaching efficiency and leaching rate of the sulphide ore such as copper pyrites and can be applied in a leaching process and a dump leaching process of a stirring tank. A certain basis for popularization and application of biological metallurgy of the sulphide ore is provided by the invention.

The invention provides biological potassium fertilizer produced by using low taste rock containing potassium and a production method for the fertilizer. The biological potassium fertilizer is prepared through the following steps of solid state fermentation treatment of the low taste rock containing potassium, processing waste of agricultural byproducts, water, earthworm and complex bacteria, biotransformation under the effect of the earthworm and housefly larvae as well as the bioleaching. On the basis of the two-step transformation method (the solid state fermentation and the bioleaching) for producing biological potassium fertilizer, the biotransformation step is added in the invention. After the solid state fermentation, biology with biotransformation function is inoculated. The conversion of the potassium in the low taste rock containing potassium is improved; therefore, the rock powder containing the potassium and agriculture waste are turned into good organic fertilizer through a plurality of transmission ways. The contents of other trace elements in the potassium fertilizer are increased. Therefore, the invention has a good market promotion prospect with an economical and practical advantage and good fertility of the potassium fertilizer.

The invention relates to a method for recovering at least one metal present within a material, said material possibly including iron, said method including a step of supplying a ferrous ion, a step of supplying a ferric ion, and a step of bioleaching at least one metal present in the material by the ferric ions, each one of the steps being implemented by a particular bacterial population.

The invention relates to a bacillus and a method for bio-leaching of scandium from scandium-containing minerals by virtue of the bacillus. The method comprises the following steps: crushing the scandium-containing minerals and grinding the scandium-containing minerals until grain size is 0.037-0.074mm, adding obtained scandium-containing mineral powder to a microorganism-containing culture solution, controlling a pulp concentration as 1-10%, and conducting bio-leaching for 7-15 days, wherein a leaching rate is 20-50%; and centrifuging or settling-separating a leached pulp, so that a scandium-containing solution is obtained, and conducting extracting, conducting washing and conducting reverse-extracting as conventional means, so that a scandium primary concentrate is obtained. The method disclosed by the invention, which is free from the addition of acid during leaching, can reduce production cost and achieve green scandium leaching, without pollution to environment; and the scandium in a leachate can be enriched by virtue of a conventional method. The biological method is green and environment-friendly, simple in process and easy for popularization.

The invention discloses a method for leaching metal from metallic ores and a special strain in the same. The strain is metallosphaera sp. Ar-4, with the collection number being CGMCC NO.3402. Experiments prove that the strain can grow under the environment of low pH value, high temperature and hypersalinity, can be used for leaching copper ions from the copper pyrite, with leaching rate of 10.6%, and can be also used for leaching iron ions from the pyrite (sulfur concentrate), with leaching rate of 2.9%. The high temperature ore-leaching strain improves the oxidation efficiency of the sulfide from at least two aspects as follows: first, with temperature rise, the reaction rate is increased; and second, temperature rise can expand the range of extraction of metal from a few minerals, thus marking up for the defects of unsuccessful leaching of a few minerals by the mesophilic strain, high investment, low efficiency and the like. The strain is especially suitable for the minerals with low leaching efficiency, such as copper pyrite. In addition, the strain has superstrong acid resistance; therefore, generated acidity can not affect the effects of the strain in the bioleaching process and can further improve the leaching efficiency.

The invention discloses an unmarked gene knock-out method of extremely acidophilic thiobacillus ferrooxidans based on the principle of homologous recombination. The method comprises the following steps of: constructing initial plasmids, suicide plasmids containing homologous fragments at upstream and downstream parts of target genes to be knocked out, and induction plasmids containing yeast endonuclease I-SceI genes; jointing and transferring the suicide plasmids and the induction plasmids to acidophilic thiobacillus ferrooxidans; and screening and identifying single commutators generating homologous recombination for the first time and double-exchange mutant strains generating homologous recombination for the second time. The method disclosed by the invention realizes the unmarked gene knock-out of acidophilic thiobacillus ferrooxidans for the first time, can realize the purpose of quickly, stably and efficiently knocking out the genes of the thiobacillus ferrooxidans, and can be used for researching the functional and metabolic mechanisms of the genes of the thiobacillus ferrooxidans, improving the genetic characters and constructing efficient bioleaching engineering bacteria; and moreover, the obtained mutant strain does not carry any resistance gene, thus the obtained mutant strain not only can be used as an original strain to knock out and improve genes in subsequent different sites, but also can be safely used for large-scale industrial production.

The invention relates to a new alicyclobacillus strain and an application thereof in bioleaching. The conservation number of the screened alicyclobacillus strain is CGMCC 4500; and the strain is cultured at the temperature of 25-35 DEG C and grows within the pH range of 1.5-5.0. The strain can be applied in the bioleaching field such as pyrite leaching. The alicyclobacillus strain has an acidophilic character, and can grow by taking ferrous ions as an energy matrix and fixed CO2 as a carbon source and meanwhile can rapidly grow by virtue of organicnutrition, thus the strain is suitable for large-scale amplification culture so as to be applied in the bioleaching field. Studies show that the new alicyclobacillus strain has the advantages of high leaching rate, short leaching time, no environmental pollution and the like, and metal ions therein have high tolerance and are free from inhibition of organic matters in the system.

A method for improving bioleaching effect of municipal solid waste incineration flying ash relates to a method for leaching the heavy metal in the waste incineration flying ash by the combination of biological desiliconization and bioleaching. The specific steps include: using silicate bacteria to conduct biological desiliconization treatment on the flying ash and damaging the mineral crystal lattice in the flying ash to release more metal oxide; and using Aspergillus niger to conduct bioleaching on the flying ash after the desiliconization treatment, thus remarkably improving the leaching effect of heavy metal in the bioleaching process due to the full contact reaction between more heavy metal oxide and the organic acid generated by the Aspergillus niger. The method is simple and convenient in operation, high in efficiency, economical and feasible and safe, is an environment-friendly effective method for removing the heavy metal in waste incineration flying ash; and leaching toxicity thereof is far lower than the authentication standard of hazardous wastes and the flying ash can enter a landfill yard or is prepared for further resource recycling.

The invention provides a heavy metal polluted soil remediation device. The device comprises a peristaltic pump, a bioleaching reactor, a micro-pore filtering column, an adjusting groove and a plant processing groove, which are sequentially connected with one another through a communication pipeline to form a ring, wherein a sample feeding opening is arranged at the top of the bioleaching reactor; an agitator is arranged inside the bioleaching reactor; an aeration device is arranged on the outer wall of the bioleaching reactor; a sample discharging opening is arranged at the bottom of the bioleaching reactor; an air outlet of the aeration device is arranged inside the bioleaching reactor; a first control valve is arranged between the bioleaching reactor and the micro-pore filtering column; a second control valve is arranged between the adjusting groove and the plant processing groove; and a third control valve is arranged at the bottom of the plant processing groove. The invention further provides a method for processing heavy metal polluted soil by the device. The device has the advantages of simple structure, convenience for use, low utilization cost, high processing efficiency and good processing effect.

The invention relates to a method for improving sludge dewatering performance by combining bioleaching and dual conditioners, and belongs to the technical field of sludge treatment. The method comprises the following steps of: under the condition of adding sufficient substrates, culturing and domesticating autochthonous bacteria in sludge, and using the autochthonous bacteria as inoculum; adding the inoculums into the residual sludge, and performing bioleaching on the sludge under the conditions of aerob, stirring and proper substrate until the pH of the sludge is about 2; adding saturated NaOH solution into the leached sludge to adjust the pH of the sludge to between 6 and 7; adding aluminium polychlorid and polyacrylamide into the sludge to condition the sludge; and performing mechanical dewatering on the treated sludge by a plate-and-frame filter pressing or centrifugal dewatering method to obtain the dewatered sludge with the moisture content between 65 and 75 percent. The bio-acidification and the dual conditioners are combined to improve the sludge dewatering performance, so the reaction efficiency can be improved, the reaction time can be shortened, the treatment capacity can be improved, and the sludge treatment cost can be reduced.

A method of recovering a precious metal from a sulphide mineral slurry which contains the precious metal which includes the steps of subjecting the slurry to a bioleaching process, supplying a feed gas which contains in excess of 21% oxygen by volume to the slurry, and recovering precious metal from a bioleach residue of the bioleaching process.

The invention provides a method for removing a heavy metal Cr from sludge by bioleaching, relates to technology for processing municipal solid waste, and aims to solve the problem of restriction on recycling the sludge, which contains higher heavy metal Cr content, of municipal sewage plants in agriculture and forestry. The method comprises the following steps of: adding a proper amount of cultured and domesticated inoculating solution in a reaction system, wherein the ratio of the substrate concentration to the sludge quantity (dry weight) is controlled to be 0.5-0.8; the sludge concentration is 15-25 g/L; the dissolved oxygen concentration is 7.5-9.0 mg/L; the reflux ratio of the sludge is 10-20 percent; and the temperature is controlled to be 25-30 DEG C; and supplementing water which is evaporated in a reactor regularly. By using the method, the removal rate of the heavy metal Cr reaches 45-55 percent through the bioleaching period.

The invention relates to a method for processing heavy metal in sludge, particularly a method for removing heavy metal in sludge by recycling residual sludge after leaching and needing no additional strains. In the process of sludge reaction, by controlling the reaction temperature to 28-35 DEG C, the pH value to 2-2.5, and the dissolved oxygen to 2-3 mg/L, the effect of removing heavy metal in sludge is guaranteed. Compared with the techniques of processing heavy metal in sludge in the prior art, especially a traditional bioleaching method, the use of the method disclosed herein saves the culture time of strains, and reduces the difficulties of operators for operation management. According to the invention, the invention guarantees that improved strains have strong activity in every processing stage, residual partial sludge after processing is used as the strain, thus the reaction of removing heavy metal in sludge through a biological method can be guaranteed to carry out. The method has the advantages of simple structure, convenient operation management, low production cost and the like, and has good supporting effect of processing and utilizing urban sludge.

The invention discloses a method for removing heavy metal Cu in sludge of an urban sewage treatment plant in a bioleaching mode, by means of the method, the problem that sludge of the urban sewage treatment plant contains much heavy metal Cu is solved, and the treated sludge can serve as fertilizer for agricultural utilization. The method includes the following specific steps that original thiobacillus in the sludge is enriched and cultured, acclimated sludge is obtained, the acclimated sludge serves as the inoculum and is added to raw sludge, Na2S2O3 and FeSO4 substrates are fed, the feeding amount of Na2S2O3 is controlled to be 3-5 g/L, the feeding amount of FeSO4 is controlled to be 4-6 g/L, air is blown into the sludge at the speed of 1.0-1.5 L/(min-L), stirring is conducted at a certain rotation speed, the temperature is controlled to be 20-30 DEG C, and the sludge is subjected to bioleaching; after bioleaching is conducted for 3-4 days, the removal rate of the heavy metal Cu reaches 90% or above. The method is reasonable in design and high in practicability.

The invention discloses an efficient separation and purification process for a bioleaching solution with low-content nickel and cobalt. The efficient separation and purification process comprises the following steps: (1) taking a macroporous adsorption resin as a supporter, taking the saponified P507-Cyanex272 double-extraction agent as an active component of an extraction-elution resin, taking ethyl alcohol or petroleum ether as a diluent, and preparing an extraction-elution resin with the double-extraction agent; (2) filling an extraction-elution resin column with the prepared extraction-elution resin, adjusting the pH value of the bioleaching solution with nickel and cobalt to be in a range from 3.5 to 5.0, and eluting the extraction-elution resin column to carry out charging; (3) carrying out gradient elution on the extraction-elution resin column, and carrying out two-section gradient elution by virtue of an HAc-NaAc buffer solution with a pH value of 3.0-5.5 and sulphuric acid with a pH value of 1.0-3.5 separately; and (4) concentrating the eluted cobalt back-extraction solution, and then carrying out electrolytic deposition to obtain a cathode cobalt product. Compared with a conventional extraction separation method or ion exchange method, the efficient separation and purification process disclosed by the invention is multistage and efficient, and further has the advantages of being high in selectivity, good in mass transfer effect and the like, increases the separation and purification efficiency of the cobalt solution, and is simple in flow, easy to operate and low in environmental pollution.

The invention relates to a selective bioleaching process of a high-sulphur/copper ratio secondary copper sulphide ore. In the process, microorganisms are utilized to leach the high-S/Cu ratio low-grade secondary copper sulphide ore, and the oxidation-reduction potential in the leaching process is controlled through the measures of regulating the pH, the dripping intensity, the fallow system, the air permeability, the breeding of dominant species, and the like so as to realize the selective leaching of the secondary copper sulphide ore. The process has short flow, simple equipment, low investment, low cost, no pollution, high recovery rate and adjustable production scale, can treat low-grade copper ore resources which cannot be treated by using the traditional selecting and smelting process, the resource utilization range is enlarged, and the comprehensive recovery level of copper metal is improved.

The invention belongs to the field of hydrometallurgy and particularly relates to a method of promoting bioleaching of copper pyrites by adding a nonionic surfactant. The technical scheme is as follows: the method comprises the following steps: crushing and grinding a copper pyrites sample and sterilizing the sample by ultraviolet light to obtain a product as a leaching sample; putting the leaching sample in a 9L basic salt solution sterilized; inoculating ferrous oxide thiobacillus; then, adding polyethylene glycol, wherein the addition of polyethylene glycol is 30-90mg/L; adjusting the initial leaching pH to 1.8-3.5 by using dilute sulphuric acid; under the condition of 25-35 DEG C and 150-180r/min, oscillating and leaching for 18-25 days; and adding polyethylene glycol to at least increase the leaching ratio of copper pyrites by 1.36 times. The invention provides a novel path for increasing the bioleaching rate of low-grade copper pyrites and is of important meaning to promote large-scale industrial application of a low-grade copper pyrite bioleaching process.

The invention discloses a bioleaching method for anaerobic digested sludge and belongs to the technical field of sludge treatment. Bioleaching work flora is compounded by introducing new microbial strains, continuous domestication is performed, an inoculum obtained through domestication is mixed with the anaerobic digested sludge for bioleaching treatment, the new microbial strains are used for degrading small-molecular organic acids and secreting surface active materials to rapidly remove EPSs (extracellular polymeric substances) wrapping surfaces of sludge cells, bioleaching reaction time isshortened to 12-24 h, the sludge obtained after bioleaching directly enters a plate-and-frame filter press for dehydration, and a mud cake with water content lower than 60% is obtained. The method adopts simple process, no chemical reagent is needed due to complete dependence on action of microbes, and the method has the advantages of high dehydration efficiency, low operation cost and low technological operation difficulty.

The invention discloses a continuous enlarging cultivation device for mineral-bioleaching microorganisms. The cultivation device comprises a cylinder which is formed by sequentially connecting an upper cylinder body, a middle cylinder body and a lower cylinder body, wherein the upper cylinder body can collect feed liquid which is discharged due to overflowing, the middle cylinder body can continuously cultivate the microorganisms in an enlarged mode, and the lower cylinder body can collect discharged precipitates. A detachable multi-layer filler assembly is arranged in the middle cylinder body, the multi-layer filler assembly is composed of a multi-layer filler box and filler which is arranged in the filler box, a heater, a nutrient solution distributing plate and an aeration device are arranged below the multi-layer filler assembly, and the aeration device is arranged below the nutrient solution distributing plate. The cultivation device is simple in design, continuous cultivation canbe achieved, the concentration of the microorganisms in a mature bacteria solution can be improved, and while continuous production of the high-concentration bacteria solution is maintained, the problem about the loss of strains in a reactor is effectively eased. The cultivation efficiency of the mineral-bioleaching microorganisms is improved, and the device has the advantages of being safe, efficient, low in space occupation, low in power consumption, simple and easy in operation and capable of achieving combined cultivation of a plurality of cultivation devices.

The present invention is directed to microbiological processes for the oxidative treatment of refractory gold and base metal ores and concentrates, and particularly, an apparatus for testing refractory gold and sulfidic base metal ores for their suitability to heap biooxidation or bioleaching processes. The invention can be used to simulate heap biooxidation. This apparatus incorporates features of heap biooxidation and may be used to generate engineering data for creating detailed process and engineering designs. The invention can be used to develop a select population of bacteria geared to optimize biooxidation of a specific refractory ore.